#!/bin/bash

# The purpose of this test script is to determine if create-diff-object can

# properly recognize object file equivalence when passed the same file for both

# the original and patched objects.  This verifies that create-diff-object is

# correctly parsing, correlating, and comparing the different elements of the

# object file.  In practice, a situation similar to the test case occurs when a

# commonly included header file changes, causing Make to rebuild many objects

# that have no functional change.

# This script requires a built kernel object tree to be in the kpatch cache

# directory at $HOME/.kpatch/obj

#set -x

OBJDIR="$HOME/.kpatch/obj"

SCRIPTDIR="$(readlink -f $(dirname $(type -p $0)))"

TEMPDIR=$(mktemp -d)

RESULTSDIR="$TEMPDIR/results"

VMVLINUX="/usr/lib/debug/lib/modules/$(uname -r)/vmlinux" # path for F20

if [[ ! -d $OBJDIR ]]; then

	echo "please run kpatch-build to populate the object tree in $OBJDIR"

fi

cd "$OBJDIR" || exit 1

for i in $(find * -name '*.o')

do

	# copied from kpatch-build/kpatch-gcc; keep in sync

	case $i in

		*.mod.o|\

		*built-in.o|\

		*built-in.a|\

		vmlinux.o|\

		.tmp_kallsyms1.o|\

		.tmp_kallsyms2.o|\

		init/version.o|\

		arch/x86/boot/version.o|\

		arch/x86/boot/compressed/eboot.o|\

		arch/x86/boot/header.o|\

		arch/x86/boot/compressed/efi_stub_64.o|\

		arch/x86/boot/compressed/piggy.o|\

		kernel/system_certificates.o|\

		.*.o)

		continue

		;;

	esac

	# skip objects that are the linked product of more than one object file

	[[ $(eu-readelf -s $i | grep FILE | wc -l) -ne 1 ]] && continue

	$SCRIPTDIR/../kpatch-build/create-diff-object $i $i /usr/lib/debug/lib/modules/$(uname -r)/vmlinux "$TEMPDIR/output.o" > "$TEMPDIR/log.txt" 2>&1

	RETCODE=$?

	# expect RETCODE to be 3 indicating no change

	[[ $RETCODE -eq 3 ]] && continue

	# otherwise record error

	mkdir -p $RESULTSDIR/$(dirname $i) || exit 1

	cp "$i" "$RESULTSDIR/$i" || exit 1

	case $RETCODE in

		139)

			echo "$i: segfault" | tee 

			if [[ ! -e core ]]; then

				echo "no corefile, run "ulimit -c unlimited" to capture corefile"

			else

				mv core "$RESULTSDIR/$i.core" || exit 1

			fi

			;;

		0)

			echo "$i: incorrectly detected change"

			mv "$TEMPDIR/log.txt" "$RESULTSDIR/$i.log" || exit 1

			;;

		1|2)

			echo "$i: error code $RETCODE"

			mv "$TEMPDIR/log.txt" "$RESULTSDIR/$i.log" || exit 1

			;;

		*)

			exit 1 # script error

			;;

	esac

done

rm -f "$TEMPDIR/log.txt" > /dev/null 2>&1

# try to group the errors together in some meaningful way

cd "$RESULTSDIR" || exit 1

echo ""

echo "Results:"

for i in $(find * -iname '*.log')

do

	echo $(cat $i | head -1 | cut -f2-3 -d':')

done | sort | uniq -c | sort -n -r | tee "$TEMPDIR/results.log"

echo "results are in $TEMPDIR"